Mechanical seal



Jan. 10, 1950 F. B. o|=cs|zs 23,189

MECHANICAL SEAL Original Filed Dec. so, 1946 & LN

1 mi I J. INVENTOR y. ATTORNEY Reissued Jan. 10, 1950 I ,f Re 23,189

UNITED STATES PATENT OFFICE MECHANICAL SEAL h'ederlclrnenjamin Porges, Manchester, England,

assignor to Flexibox Limited, Manchester, England, a British company Original No. 2,455,700, dated December I, 1948,

Serial No. 719,153, December 30, 1946. Application for reissue June 15, 1949, Serial No. 99,238. In Great Britain November 22, 1946 1 Claims. (01. ass-41.15)

Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue 1 This invention relates to mechanical seals for making a fluid or gastight joint between a revolving shaft and a stationary surface and has for its object to provide an improved mechanical temaiepart.

Referring to the accompanying explanatory drawings:

Figure 1 is a sectional elevation of a mechanical seal constructed and arranged in accordance seal which is compact, simple to assemble and 5 wi h th s vention. Figure 2 shows a modificamaintain and capable of being readily fitted in Eon. fFigure'h3 is a gggntientary sectional elevaplace of an existing mechanical seal. on o a fur er mo ca ion.

It is known to provide a mechanical seal for The seal comprises a stationary seal ring 3 making a fluid-tight joint between a revolving between a shoulder on which and a shoulder on shaft and a stationary surface in which a spring thedfi etfi covirgtls a 82361316 sealltilwfhich may he hears at one end against a shoulder on the shaft ma e o y i e 10 ru W 10 OrmS a rend t th other end against ring around t silient cushion for the seal device, makes a leakshaft having a static seal located in an internal W21 1 gfii t e ili g I anghthei cover 11;}, recess in said ring, which makes frictional enan 8X61 S 511 0 B11 110 10B 011 8 8 gagement with said ring and the shaft so as to 15 service to prevent the ring from rotating in the ar r std-W25 iiiiiti 2. 2:: remarrie sroary sea rng spresse y esprng s e against the stationary seal ring which is held 3 1 l i l ze e tha the latter does against rotation. 110 11m See s re It is important to prelventtany szto'inigs oil) 35116 sio'fl g figggywsfi c h o n 4 gigs)? tstlleevelliiliga cartinshaft by the spring w en he la r e g e e e sp g as passed along the haft during the assembly of t an in'terference fit. Within the ring 4 is a static seal and it is also important that the rotary seal al which may be made of Synthetic rubber. ring should not have any rotary movement relaa dtiwhich fltis m a groove in the ring 4 so D tively to the shaft, as such tmovement vtvlill i1;:2- s g a ft g fl i'le 3 x388 Zion? tgie surfac: If the s it in the static seal within he ring or t e r g 0 e sp g as an gradually scoring which will re interference 0n the c0118.! 9 grips suit eventually in the failure of the rotary seal. the shaft adjacent o the u der ID on the It is important also to prevent the stationary 3o Shaft against which F end of the Spring bearsseal ring from rotating in the cover which would agizg g i g fi g zt gf in lzy hgwe 13 filifikened have similar consequences. g. w c as an The object of the present invention is to prointerference fit with the f of e Sp 6' advide an improved construction of rotary seal in Jacent to h shoulder x which the above points are efiectively dealt with. The hand e l'ight left) of the spring 8 In accordance with my present invention, the J5 such that any movement of the ring spring has sleevelike parts projecting and fitting gz gg tgz zgg g s g z gg i ggi gzfig g fi g gz js f gjf g f izf z $5322 3: the sleevelike projection 5 to twist the spring in der on the shaft against which the end of the a direction which tightens its convolutions and S rm bears and the other part being in the 40 so increases its grip on both ends with the result p g that relative movement of the ring 4' on the shaft form 01 a sleevelike extension of the rotary seal a is effectively prevente It is to be noted that ring which z i g the shaft which thecoil spring and the interference fits constibears gains the s (nary seal he spring tute [a sole] means for causing the seal ring to being n interference fit on Sam sleevgs and its turn with the revolving member. Moreover, in convolutions being of such hand (i. e. right or the arrangement just described the can spring left hand) that any tendency of the rotary seal and the interference fits constitute the principal ring to turn relatively to the shaft causes the means for causing the seal ring to turn the shaft. spring to be wound up and 5 close upon and The spring 6 therefore effectively drives the rip suc slee s o ht y a d thus resist seal ring 4 at all times and obviates any scoring sueh sy interference fit hereinbemre of the shaft by the static seal 1. As the bore mentioned is meant that before interfitting the oi the spring 5 is muchgreater thanthe diameter parts, the external diameter of the male part is or the shaft 8, there is little possibility of the always larger than the internal diameter of the {shaft "being scored when the spring is being placed in position thereon.

salsa 3 7 It will be seen that the rotaryseal ring tits a\lerence flt witha partof the rotary seal ring,

plain shaft and that the installation of the de-. vice requiresno tools except those for the studs securing the cover 2. What I claim is: 1. A mechanical seal for making a fluidtight Joint between a revolving member and a stationthe convolutions of the spring being of such hand with respect. to the direction of rotation that any tendency of the rotary seal ring to turn relatively to the shaft causes the spring to more tightly grip the parts which have interference ary surface comprising, in combination, a coil spring around the revolving member, a rotary seal ring around the revolving member, a stationary surface against which the rotary seal ring bears under the pressure of said spring, characterized in, that one end of the spring has an I interference fit with a part of the revolving member and the other end an interference fit ency of the rotary seal ring to turn relatively'to the revolving member causes the spring to more tightly grip the parts which have interference fits with its ends and resist such tendency, the coil spring and interference fits constituting [a sole] means for causing the seal ring to turn with the revolving member.

2. In a mechanical seal as claimed in claim 1, a stationary seal ring between the rotary seal ring and the stationary surface, a static seal between the stationary seal ring and the stationary surface, and a pin extending between the stationary seal ring and stationary surface to prevent relative turning movements thereof.

3. In a mechanical seal as claimed in claim 1,

I a sleeve around and revolving with a shaft constituting the revolving member, the sleeve having a thickened part which is an interference fit with the end'of the spring.

4. A mechanical seal as claimed in claim 3 in which the sleeve is in the form of I a split collar.

5. A mechanical seal for making a fluidtight foint between a rotatable shaft and a stationary surface comprising, a coil spring around-said shaft, a rotary seal ring around the shaft, means between the ring and the shaft in frictional sealing engagement therewith, a stationary surface against which the rotary seal ring bears under the pressure of said spring, one end of said spring having an interference fit with a part of the shaft and the other end of the spring having an interfits with its ends and resist such tendency, the

coil spring and interference fits constituting the principal means for causing the seal ringto turn with the shaft. f p v 6. A mechanicalseal for making a fluidtight joint between 'a rotary shaft and a stationary surface comprising, a coil, spring around the shaft, a rotary seal ring around the shaft, said seal ring having a portion extending longitudinally thereof constituting a sleeve surrounding the shaft, means between the ring and the shaft in frictional sealing engagement therewith, a stationary surface against which the rotary seal ring bears under the pressure of said spring, one

spect to the direction of rotation that any tendency, of the rotary seal ring to turn relatively to the shaft causes the spring to more tightly grip the part of the shaft and the sleeve extension which have interference fits with its ends and resist such tendency, the coil, spring and interference fits constituting the principal means for causing the seal ring to turn with the shaft.

7. A-mechanical seal as claimed in claim 5 in which a sleeve is disposed around and in frictional engagement with the shaft so as to rotate therewith and wherein the said one end of said spring has an interference fit with said sleeve.

FREDERICK BENJAMIN PORGES.

REFERENCE S CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

